The class IX students of a certain public School wanted to give a farewell party to the outgoing student of class X. They decided to purchase two kinds of sweets, one costing ₹350 per kg and the other costing ₹ 440 per kg. They estimated that 36 kg of sweets were needed. If the total money spent on sweet was ₹ 14,000, find how much sweets of each kind they purchased.

Let first sweet purchased be x kg and second be y kg.

Then, x + y = 36 or y = 36 - x ………………….(1)

Cost of first sweet = ₹ 350 per kg

Cost of second sweet = ₹ 440 per kg

Total cost of sweets will be 350x + 440y.

Total money spent on sweet = ₹ 14,000

⇒ 350x + 440y = 14000

Substituting the value of y from (1) in above equation we get,

⇒ 350x + 440(36 - x) = 14000

⇒ 350x + 15840 - 440x = 14000

⇒ 15840 - 90x = 14000

⇒ 90x = 15840 - 14000

⇒ 90x = 1840

⇒ x = $\dfrac{1840}{90}$

⇒ x = 20.44 ≈ 20.

Substituting this value of x in eq (1)

⇒ y = 36 - x

⇒ y = 36 - 20

⇒ y = 16.

Hence, the sweet costing ₹350 per kg purchased was 20 kg and the one costing ₹440 per kg was 16 kg.